Accurate sensors to monitor temperature are used for thermal management of micro-processors. Most System-on-Chip (SoC) solutions use some kind of temperature tracking, in order to optimize or control the performance of certain functions. At times, where phones merge with mobile computers, relevant applications of thermal sensors include also mixed-signal functions, like RF (radio frequency) or audio power amplifiers. Some thermal sensors exhibit a sensing slope between temperature and an output code, where the sensing slope has full dependency on subthreshold factor (SF) of a metal oxide semiconductor field effect transistor (MOSFET). This SF is a process technology dependent parameter that has wide variation during manufacturing. This wide variation in the SF leads to sensing inaccuracies.